diff --git a/changelog.md b/changelog.md
index 729aa5a..68b88da 100644
--- a/changelog.md
+++ b/changelog.md
@@ -50,3 +50,7 @@
 2025-11-08  move wiki data loading into a built workspace dependency and add provider tests  wiki-data-reader item-optimizer/src/itemDataProvider.ts item-optimizer/src/__tests__
 2025-11-08  add wiki snapshot refresh + parser/update scripts with hero ingestion  wiki-data-reader/scripts wiki-data-reader/snapshots
 2025-11-09  fetch remote item icon URLs from wiki snapshots and remove local PNGs  wiki-data-reader/scripts item-optimizer/src
+
+2025-12-18  add mobile tap-to-toggle detail previews in Item Gallery  item-optimizer/src/components/ItemGallery.tsx
+2025-12-19  clamp tooltip position and anchor mobile taps to item bounds  item-optimizer/src/components/ItemGallery.tsx item-optimizer/src/utils/tooltipUtils.ts
+2025-12-20  keep Item Gallery detail sticky on mobile and disable tooltip taps  item-optimizer/src/components/ItemGallery.tsx
diff --git a/item-optimizer/src/components/ItemGallery.tsx b/item-optimizer/src/components/ItemGallery.tsx
index b1752b6..da3a2c5 100644
--- a/item-optimizer/src/components/ItemGallery.tsx
+++ b/item-optimizer/src/components/ItemGallery.tsx
@@ -1,4 +1,4 @@
-import { useState, useMemo } from "react";
+import { useEffect, useMemo, useState, type MouseEvent } from "react";
 import { useAppDispatch, useAppSelector } from "../hooks";
 import { clearTooltip, setTooltip } from "../slices/tooltipSlice";
 import type { Item, ItemOverride } from "../types";
@@ -36,6 +36,24 @@ export default function ItemGallery({ items, heroes, attrTypes }: Props) {
   const dispatch = useAppDispatch();
   const overrideVersion = useAppSelector((s) => s.input.present.overrideVersion);
   const overrides = useMemo(loadLocalOverrides, [overrideVersion]);
+  const isMobile = useMemo(() => {
+    if (typeof window === "undefined") return false;
+    if (window.matchMedia?.("(pointer: coarse)")?.matches) return true;
+    return window.innerWidth < 640;
+  }, []);
+
+  useEffect(() => {
+    return () => {
+      dispatch(clearTooltip());
+    };
+  }, [dispatch]);
+
+  function handleItemClick(it: Item) {
+    setSelected(it);
+    if (isMobile) {
+      dispatch(clearTooltip());
+    }
+  }
 
   const filtered = items.filter(
     (it) =>
@@ -47,7 +65,12 @@ export default function ItemGallery({ items, heroes, attrTypes }: Props) {
     <div className="glass-card space-y-6 rounded-xl shadow-lg p-4 sm:p-6 bg-white dark:bg-gray-800 dark:border-gray-700">
       <h2 className="text-2xl font-bold text-gray-900 dark:text-gray-100 sm:text-3xl">Configuration</h2>
       <div className="relative">
-        <div>
+        <div
+          className={`space-y-2 ${
+            isMobile ? "sticky top-0 z-10 bg-white dark:bg-gray-800 pb-4" : ""
+          }`}
+          data-testid="item-detail-panel"
+        >
           {selected && (
             <div className="space-y-2">
               <div className="space-y-1">
@@ -210,10 +233,20 @@ export default function ItemGallery({ items, heroes, attrTypes }: Props) {
                 <button
                   key={idx}
                   type="button"
-                  onClick={() => setSelected(it)}
-                  onMouseEnter={(e) => dispatch(setTooltip({ item: it, x: e.clientX, y: e.clientY }))}
-                  onMouseMove={(e) => dispatch(setTooltip({ item: it, x: e.clientX, y: e.clientY }))}
-                  onMouseLeave={() => dispatch(clearTooltip())}
+                  onClick={() => handleItemClick(it)}
+                  onMouseEnter={
+                    isMobile
+                      ? undefined
+                      : (e: MouseEvent<HTMLButtonElement>) =>
+                          dispatch(setTooltip({ item: it, x: e.clientX, y: e.clientY }))
+                  }
+                  onMouseMove={
+                    isMobile
+                      ? undefined
+                      : (e: MouseEvent<HTMLButtonElement>) =>
+                          dispatch(setTooltip({ item: it, x: e.clientX, y: e.clientY }))
+                  }
+                  onMouseLeave={isMobile ? undefined : () => dispatch(clearTooltip())}
                   className="relative flex flex-col items-center gap-1 p-2 rounded border dark:border-gray-700 bg-white dark:bg-gray-900 hover:bg-gray-100 dark:hover:bg-gray-800"
                 >
                   {overrides[it.name] && (
diff --git a/item-optimizer/src/components/__tests__/ItemGallery.test.tsx b/item-optimizer/src/components/__tests__/ItemGallery.test.tsx
index 86401d9..46c2ddf 100644
--- a/item-optimizer/src/components/__tests__/ItemGallery.test.tsx
+++ b/item-optimizer/src/components/__tests__/ItemGallery.test.tsx
@@ -1,6 +1,7 @@
 /* @vitest-environment jsdom */
 import "@testing-library/jest-dom";
 import { fireEvent, render, waitFor } from "@testing-library/react";
+import { vi } from "vitest";
 import { Provider } from "react-redux";
 import ItemGallery from "../ItemGallery";
 import store from "../../store";
@@ -124,4 +125,34 @@ describe("ItemGallery", () => {
     fireEvent.click(getByText("Save"));
     expect(localStorage.getItem("localOverrides")).toBe("{}");
   });
+
+  it("keeps the detail panel sticky on mobile and avoids tooltip taps", () => {
+    const originalMatchMedia = window.matchMedia;
+    window.matchMedia = vi.fn().mockImplementation((query) => ({
+      matches: query === "(pointer: coarse)",
+      media: query,
+      onchange: null,
+      addListener: vi.fn(),
+      removeListener: vi.fn(),
+      addEventListener: vi.fn(),
+      removeEventListener: vi.fn(),
+      dispatchEvent: vi.fn(),
+    }));
+
+    const { getByText, getByTestId } = render(
+      <Provider store={store}>
+        <ItemGallery items={items} heroes={heroes} attrTypes={attrTypes} />
+      </Provider>,
+    );
+
+    expect(getByTestId("item-detail-panel")).toHaveClass("sticky");
+
+    const secondItem = getByText("Two").closest("button")!;
+    fireEvent.click(secondItem);
+
+    expect(store.getState().tooltip).toBeNull();
+    expect(getByText("ability")).toBeInTheDocument();
+
+    window.matchMedia = originalMatchMedia;
+  });
 });
diff --git a/item-optimizer/src/utils/__tests__/tooltipUtils.test.ts b/item-optimizer/src/utils/__tests__/tooltipUtils.test.ts
new file mode 100644
index 0000000..af1963c
--- /dev/null
+++ b/item-optimizer/src/utils/__tests__/tooltipUtils.test.ts
@@ -0,0 +1,34 @@
+/* @vitest-environment jsdom */
+import { getTooltipStyle } from "../tooltipUtils";
+
+describe("getTooltipStyle", () => {
+    const originalWidth = Object.getOwnPropertyDescriptor(window, "innerWidth");
+    const originalHeight = Object.getOwnPropertyDescriptor(window, "innerHeight");
+
+    afterEach(() => {
+        if (originalWidth?.get) {
+            Object.defineProperty(window, "innerWidth", originalWidth);
+        }
+        if (originalHeight?.get) {
+            Object.defineProperty(window, "innerHeight", originalHeight);
+        }
+    });
+
+    it("keeps tooltip within viewport when space is limited", () => {
+        Object.defineProperty(window, "innerWidth", { value: 280, configurable: true });
+        Object.defineProperty(window, "innerHeight", { value: 200, configurable: true });
+
+        const style = getTooltipStyle(10, 10, { width: 260, height: 180, offset: 12 });
+        expect(style.left).toBe(12);
+        expect(style.top).toBe(12);
+    });
+
+    it("flips position and clamps to max viewport space", () => {
+        Object.defineProperty(window, "innerWidth", { value: 360, configurable: true });
+        Object.defineProperty(window, "innerHeight", { value: 300, configurable: true });
+
+        const style = getTooltipStyle(350, 280, { width: 200, height: 180, offset: 12 });
+        expect(style.left).toBeLessThanOrEqual(148);
+        expect(style.top).toBeLessThanOrEqual(108);
+    });
+});
diff --git a/item-optimizer/src/utils/tooltipUtils.ts b/item-optimizer/src/utils/tooltipUtils.ts
index 0502538..45e93ee 100644
--- a/item-optimizer/src/utils/tooltipUtils.ts
+++ b/item-optimizer/src/utils/tooltipUtils.ts
@@ -13,7 +13,7 @@ export interface TooltipStyleOptions {
 export function getTooltipStyle(
     x: number,
     y: number,
-    options: TooltipStyleOptions = {}
+    options: TooltipStyleOptions = {},
 ): React.CSSProperties {
     const winW = window.innerWidth;
     const winH = window.innerHeight;
@@ -28,6 +28,10 @@ export function getTooltipStyle(
     if (top + TOOLTIP_HEIGHT > winH) {
         top = y - TOOLTIP_HEIGHT - OFFSET;
     }
+    const maxLeft = Math.max(OFFSET, winW - TOOLTIP_WIDTH - OFFSET);
+    const maxTop = Math.max(OFFSET, winH - TOOLTIP_HEIGHT - OFFSET);
+    left = Math.min(Math.max(left, OFFSET), maxLeft);
+    top = Math.min(Math.max(top, OFFSET), maxTop);
     return {
         left,
         top,